Collaborative Research: Peripheral East Antarctic Ice as a Unique Recorder of Climate Variability during the Last Interglacial

合作研究：南极东部外围冰作为末次间冰期气候变化的独特记录者

• 批准号: 2035637
• 负责人: Clay Tabor
• 金额: $ 28.94万
• 依托单位: University of Connecticut
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-15 至 2024-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2035637&HistoricalAwards=false
• 关键词: Collaborative; Research; Peripheral; East; Antarctic

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2).The spatial extent of the West Antarctic Ice Sheet during the last interglacial period (129,000 to 116,000 years ago) is currently unknown, yet this information is fundamental to projections of the future stability of the ice sheet in a warming climate. Paleoclimate records and proxy evidence such as dust can inform on past environmental conditions and ice-sheet coverage. This project will combine new, high-sensitivity geochemical measurements of dust from Antarctic ice collected at Allan Hills with existing water isotope records to document climate and environmental changes through the last interglacial period. These changes will then be compared with Earth-system model simulations of dust and water isotopes to determine past conditions and constrain the sensitivity of the West Antarctic Ice Sheet to warming. The project will test the hypothesis that the uncharacteristically volcanic dust composition observed at another peripheral ice core site at Taylor Glacier during the last interglacial period is related to changes in the spatial extent of the West Antarctic Ice Sheet. This project aims to characterize mineral dust transport during the penultimate glacial-interglacial transition. The team will apply high-precision geochemical techniques to the high-volume, high-resolution ice core drilled at the Allan Hills site in combination with Earth system model simulations to: (1) determine if the volcanic dust signature found in interglacial ice from Taylor Glacier is also found at Allan Hills, (2) determine the likely dust source(s) to this site during the last interglacial, and (3) probe the atmospheric and environmental changes during the last interglacial with a diminished West Antarctic Ice Sheet. The team will develop a suite of measurements on previously drilled ice from Allan Hills, including isotopic compositions of Strontium and Neodymium, trace element concentrations, dust-size distribution, and imaging of ice-core dust to confirm the original signal observed and provide a broader spatial reconstruction of dust transport. In tandem, the team will conduct Earth system modeling with prognostic dust and water-isotope capability to test the sensitivity of dust transport under several plausible ice-sheet and freshwater-flux configurations. By comparing dust reconstruction and model simulations, the team aims to elucidate the driving mechanisms behind dust transport during the last interglacial period.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

该奖项的全部或部分资金根据《2021 年美国救援计划法案》（公法 117-2）提供。末次间冰期（129,000 至 116,000 年前）南极西部冰盖的空间范围目前未知，然而，这些信息对于预测气候变暖下冰盖未来的稳定性至关重要。古气候记录和灰尘等代理证据可以了解过去的环境条件和冰盖覆盖范围。该项目将对在艾伦山收集的南极冰尘进行新的高灵敏度地球化学测量，与现有的水同位素记录相结合，以记录上一个间冰期的气候和环境变化。 然后将这些变化与尘埃和水同位素的地球系统模型模拟进行比较，以确定过去的条件并限制西南极冰盖对变暖的敏感性。该项目将检验以下假设：在最后一个间冰期期间，在泰勒冰川另一个外围冰芯地点观察到的异常火山尘成分与南极西部冰盖空间范围的变化有关。该项目旨在描述倒数第二次冰期-间冰期过渡期间矿物尘埃传输的特征。 该团队将高精度地球化学技术应用于在艾伦山钻探的大体积、高分辨率冰芯，并结合地球系统模型模拟来：（1）确定泰勒间冰中是否发现了火山尘特征在艾伦山也发现了冰川，(2) 确定末次间冰期期间该地点可能的尘埃来源，以及 (3) 探测末次间冰期期间南极西部缩小时的大气和环境变化冰盖。该团队将对之前从艾伦山钻出的冰进行一系列测量，包括锶和钕的同位素组成、微量元素浓度、灰尘尺寸分布以及冰芯灰尘的成像，以确认观察到的原始信号并提供更广泛的数据。灰尘传输的空间重建。与此同时，该团队将利用预测尘埃和水同位素能力进行地球系统建模，以测试几种可能的冰盖和淡水通量配置下尘埃传输的敏感性。通过比较尘埃重建和模型模拟，该团队旨在阐明末次间冰期尘埃输送背后的驱动机制。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。